Vaccines free you from the herd

source: Regione Umbria

The vaccination campaign in the U.S. got off to a slow start. One culprit is the initial obsession over "herd immunity". I wrote back in October that the focus on herd immunity is misguided:

Herd immunity draws attention to non-cooperative behavior away from the scientific achievements of vaccines. The people who stand to benefit from herd immunity don't even have immunity, as they will get sick if they come in contact with the virus. That's why I don't like the term herd immunity.

This commentary applies even if herd immunity is gained through mass vaccination. The only people to benefit from "herd immunity" are the 25% who are not immunized. A fraction of these may have conditions that make it risky to take a vaccine but most of this group will comprise of vaccine skeptics. Despite being unvaccinated, they are expected to be protected through non-exposure when a sufficient proportion of their fellow citizens has received their shots.

By contrast, someone who is vaccinated is protected. This is a direct personal benefit stemming from a personal decision. The argument for vaccination is simple: protect yourself, so you can return to normal living. You can protect yourself, regardless of what the herd does. You don't vaccinate to attain herd immunity, you vaccinate to free yourself from the herd behavior!

***

The focus on "herd immunity" reflects a technocratic bias. The discovery of herd immunity tied to a critical level of immunization is one of the shiny objects of epidemiological modeling. The mathematics is quite beautiful and simple. It's great pedagogical material. Herd immunity is also a natural goal for public health policy - the goal is better stated as eradication of the virus. If one achieves "herd immunity," the virus has been defeated.

It's not a step function - we don't need to reach the herd immunity level for the pandemic to slow down. Every vaccination cuts some transmission chains so the benefit accumulates as more people get shots.

Telling people to vaccinate for the sake of herd immunity is like telling them to do something for the benefit of others. Unfortunately, many Americans don't do things for others, as we have observed. In this case, the others are mostly people who will not reciprocate.

Tell people to vaccinate in order to sweep away the fear, and return to normal.

 

[P.S. 1/20/21 A reader rightly pointed out to me that even after vaccination, one should still wear masks, keep a distance, etc. since the vaccine is not 100% effective. I made a comment about this in a previous post - here. I said I would personally continue to take precautions, but would understand if others decide not to after vaccination. I'm making a suggestion to public health officials who believe the real-world vaccine efficacy of two doses is 90 percent or thereabouts. If it turns out that VE is lower than expected, we should be worried about too many of us returning to normal too soon.]

[P.S. 1/27/21 The Atlantic just published a piece that makes a similar point, that it may be counterproductive to tell people nothing can change even after getting vaccinated. The article also exposes a lingering problem - why are we still relying on survey responses to project how people will behave when the tech industry has all the surveillance data we need to know how people are behaving? Another important point is that the argument to allow returning to normal is founded on the belief that these vaccines are highly effective, which can be invalidated by real-world evidence.]

 

 

Comments

[Michael Droy]

It isn't really an issue about immunity at an individual level.
The herd immunity issue is really about a return to normality, a normal economy (albeit with some accelerated aspects like 20 years of progress in moving out of cities in one). And a normal health service.
Since the growing Economy and improving health service has contributed much of the increase in life expectancy that has occurred in the last 50 years, the return of this is far more important than defeating the virus.
Maybe we should be planning for a much nastier virus, but the sooner we get over the side-effects of this one the better.

As for Covid vaccination - no this is not a vaccine to self-protect; unless one is in a high risk group there is very little risk. This is a vaccine to a) protect high risk groups from you and b) return to normality.

[Kaiser]

MD: I don't understand what you're saying here. You don't get "herd immunity" by just innoculating high-risk groups. And the reason for vaccinating high-risk groups is to grant them individual immunity.

[Michael Droy]

I'm saying that Covid isn't the threat (except to the high risk groups).
The over reaction to Covid is the threat (through killing the economy and Health services)
The cure to the government and media paranoia is the vaccine and the concept of herd immunity.

Whether herd immunity to a non-threat exists of not is irrelevant. Open up the hospitals and save decades for ordinary patients instead of a few months for covid patients. Think of the vaccine as a psychological placebo for collective madness.

[Kaiser]

MD: So you're not advocating herd immunity. From what I've read, hospitals are pushing out other patients only when they are overwhelmed by dying covid patients. If people take basic precautions, reducing the spread, there will be fewer covid patients and so the other patients will get the beds.

[Michael Droy]

No the real restriction on hospitals is working practices. They just can't treat half the number of patients with half the number of staff under these conditions. It is more like 25% with 75% of staff.
And of course a big chunk of covid patients in hospitals actually arrived without it, so the restrictions are necessary for as long as Covid it perceived to be the bigger threat.
https://www.telegraph.co.uk/news/2020/12/09/exclusive-10000-patients-caught-covid-19-treated-hospital/
(refresh then quickly control-a and control-C and you can paste the whole story into say word)

(I know you have read hospitals are working heroically - but they very obviously aren't. Don't trust anything without data - I don't need to tell you that.)

If people take basic proportions the non-covid health threat just lasts a year or two longer, and the damage of a 25% capacity non-covid health services kills many many more people and takes decades off lives not months.

There was a great opportunity last summer when people could have mixed and shared early forms of the virus, not risked high hospitalisation peaks (which are seasonal) and the world could have moved on.
The next opportunity to do this is start of February (In N European climates)

[Ken]

MD: That is 10,000 out of 3.7 million, or 0.3% of cases occurred in hospitals. Virtually none. You have a hypothesis, which is that none of this is necessary, and keep grabbing at any number you can find. Unfortunately, it is wrong. The only way the UK could have avoided the level of infections is to have put an appropriate level of restrictions on, and enforced them. I'm an Australian, and we know about these things https://www.abc.net.au/news/2021-01-28/new-zealand-tops-list-as-country-with-best-covid-response/13095758

[Michael Droy]

I think you misunderstand my hypothesis.
Of course Covid is real.
The "hypothesis" is that Lock Down kills more people than it saves in the long term, and that the people killed by lockdown lose decades while the people saved gain months.

Far from talking about how best to limit infections, I am suggesting that instead they should be encouraged (in most demographic groups but with protections for others).

Btw I have travelled from UK to New Zealand (via Australia). It is no surprise that International arrivals can easily be identified by their symptoms.
Or that infection is rare even in Wellington. You get more riders in 2 days on the London train and tube system that Wellington gets in a year.